Interest in hydrogen fuel cells as power sources is continuing to grow. Exemplary hydrogen fuel cells include proton exchange membrane fuel cell (PEMFC), alkaline fuel cell (AFC), phosphoric-acid fuel cell (PAFC), solid oxide fuel cell (SOFC) and molten carbonate fuel cell (MCFC). Each of these hydrogen fuel cell can use hydrogen and oxygen as the active materials of the fuel cell negative electrode (anode) and positive electrode (cathode), respectively. Hydrogen is oxidized at the negative electrode, and oxygen is reduced at the positive electrode. Ions pass through an electrically nonconductive, ion permeable separator and electrons pass through an external circuit to provide an electric current.
Some hydrogen fuel cells utilize an external fuel source that supplies hydrogen to the fuel cell. Hydrogen generators show promise as suitable external fuel sources for hydrogen fuel cells. But the efficiency of hydrogen generators is an issue.